Two level control



J. 1 BREESE ET AL.

TWO LEVEL CONTROL Filed May 14. 1942 Patented Mar. 26,` 1946 'rWo LEVELCONTROL James L. Breese and Bruce Hayter, Santa. Fe,l

N. Mex., assignors to Oil Devices, Santa Fe, N. Mex., a limitedpartnership of Illinois Application May 14, 1942, Serial No. 442,937

6 Claims.

Our invention relates to an improvement in controls for liquids, and hasfor one purpose the provision of a control adapted for the delivery of aliquid fuel to a burner.

Another purpose is the provision of improved safety means for preventingthe accumulation of more than a predetermined relatively smallamount offuelin the bottom of a burner in the event of burner failure.

Another purpose is the provision of improved control means foraccurately controlling the now of fuel to a burner.

Another purpose is the provision of means for cutting 01T the flow offuel to a burner in response to a predetermined excess fuel in thebottom Of a burner.

wardly inclined away `from the pot bottom. Thedetails of the burner donot of themselves form part of the present invention, but we illustratefor convenience a pot type burner, lthe side walls f which are providedwith a plurality of primary air inlet apertures 4. Any suitablesecondary air inlet means may be provided at or near the top of the pot.

It will be understood that in burners of this type a liquid hydrocarbonfuel delivered to the bottom of the pot, as at 5, is vaporizd by theheat of combustion above. The vaporized hydrocarbon mixes with theprimary air delivered through the apertures 4 to form a preliminary orpartially combustible mixture, which upon being mixed with a secondaryair supply burns at or above the top of the pot.

I0 generally indicates a float chamber, with any suitable preferablyremovable top Il, I2- is a supply line extending to-the pot anddelivering fuel to a filter chamber I3, which has an upwardly extendingpassage I4, terminating in a valve seat I5 and located within orsurrounded by a sleeve IB, apertured as at I'I.

It will be understood that fuel from any suitable fuel source not hereinshown flows upwardly along the passage I4 and outwardly through thepassage I1 into the interior of the chamber I0 to form a body of liquidI8. a fuel delivery sleeve extending upwardly from the bottom of thechamber Il) and communicating with a line 20, which in turn extends bythe elbow 2I to a lower chamber 22, havingv a cover 23. The interior ofthe chamber 22 is in communication with the outer end of the fue1sur-myl line 3. i

We may provide any suitable means for maintaining a generally constantlevel of fuel in the first chamber I0. We illustrate for example a float25 adapted to control a valve stem 28, terminating in a valve element21, opposed to the valve seat I5. It will be understood that the float25 rises in response to a rise in the level of the fuel body I8, andmoves the valve stem 25 downwardly into closing position. We illustratethe float 25 ashaving an arm 28, pivoted` as at 28a'on any suitablenormally fixed support 29. An outer end 30 of the arm is in engagementwith a flange 2Gb on the upper end 26a of the valve stem 26. A spring 3|tends normally to urge the valve towards open position,

- the action of the spring being checked by the oat 25. When the levelof the fuel I8 rises with the float, the stem 26 moves toward closedposition. When the lever of the fuel I8 drops, the float 25 is eifectlveto move the valve towards open position.

It will be observed that the sleeve I9 terminates below the normal fuellevel in the chamber I0. 40 is an inner sleeve, the lower end of whichis positioned in the upper end of the sleeve I9. The' member 40 isprovided with a metering portion 4|, the bore 42 of which receives thelower end of a valve stem 43. The member 43 has a metering lower end 44,which is slotted, as at 45, to provide one or more metering apertures.It has also a conic portion 46 adapted to serve as a positive closurewhen moved against the valve seat 41. The inner sleeve 40 is aperturedas at 49 above the valve lseat 41.

48 is an exterior control knob. It will be understod that, in responseto rotation of the knob by any suitable mechanism, the stem 43 raisesandlowers, and thus varies the effective metering area of the slots 45.Thus, a controlled flow of fuel is permitted downwardly along thepasexample thermostatically responsive control,

gages a weight lever 51.

means, may be employed whereby the amount of through the bottom of thechamber I and has anopen top, as at I,'above the normal level of thefuel body I8.

52 is a float located in the lower chamber 22,

i .which cooperates with the pin 53, extending upwardly through theportion of the member 50,.y

and secured at its upper end lto a trip lever 54,

- which in turn is pivoted, as at 55, to the member 29., It has a toothor dog 56, which normally en- The weight lever carries a weight 58 andis pivoted, as at 59, to the member 29. 'I'he weight lever alsohas anoutwardly device maybe reset.

We find it advantageous to permit an actual inspection of the feeddownwardly through the.

line 20. We, therefore, illustrate an aperture or apertures 10, whichmay be closed by glass or any other suitable substance, and whichpermits the operator to watch the flow or dripping 4of fuel downwardlythrough the passage.

It will be realized that, whereas we have illustrated a practical andoperative device, nevertheless many changes may be made in the size,shape, number and disposition of parts without departing from the spiritof 'our invention. We therefore wish that the description and drawing betaken as in a broad sense illustrative or diagrammatic, rather than aslimiting us to'our precise showing.

The use and operation of our invention are as follows: 1

The level of fuel. I8 in the chamber I0 is conpot is of great practicalimportance.

Vuse of controls currently employed with pot type ume of oil in thebottom of the burnerv to burn olf. There is not enough oil inthe burnerto do any damage, and'n'ormal combustion can shortly be restored.

In practice, the provision of means of cutting off the oil supply afteronly a small amount of excess oil has accumulated in the bottom of theWith the burners, upon burner failure the pot becomes flooded with avery large amount of-oil. Draining the oil, on the one hand, is a'diicult and annoying procedure. On the other hand, the volurne of oil inthe pot bottom is so great that bur-ning'it offlis equally annoying. Itmay overheat the burner and in any event may cause cary bon deposit andheat delivery at times when heat trolled by the valve -26, 21, inresponseto movel,

to produce a lire hazard. Note that the volume ment of the oat 25. Therate of flow of fuel from- .the chamber Ill to the chamber 22 iscontrolled, either manually or. automatically, bythe valve 43, 44, 45.In the event more fuel is for any reason admitted to the pot I thancan'be burned,

and the fuel rises above the normal operatingA delivery is not desired.The time when such a pot'is most likely to go out is-when it is run at arelativelylow or pilot stagewhen heat is'not desired. If itbecomes-necessary then to burn off a great depth of oil in the bottom ofthe pot, the practical annoyance to the user is great.A

Furthermore, if the float 25 fails to close the valve 26, 21, when thefuel n the float chamber I 0 raises toa predetermined level, the fuel,when it reaches the open top 5| of the tube 50, will ow through the tubeinto the lower chamber 52 and lift the float 52 until the trip lever 54releases the weight 58V and positively closes the valve 26.

In the operation of the device it should be notedl that the inflow tothe float chamber is cut oi whenV the level of fuel in the lpot and inthe secondary chamber exceeds a predetermined and relatively lowminimum. This tripoif level is in dicated in the drawing and may belocated as much as an inch and a halfbelow the' lowest primary air inletapertures 4.. There is insuicient fuel lin the bottom of the pot at thattime may be one-tenth or less than that of the burner the pot reachesthe tripoff level, the parts are 'so proportioned that the ilo'at 52then lifts the trip f lever 54 sufliciently far to'release the dog 56 topermit the weight 58 to drop. In that connec- -tion the lever: 51strikes the reduced end 26a of the valve stem 26 and forces the valve 21into closed position, thus' cutting olf any further inow of fuel to thechamber I II. But only a relatively small volume of fuel is in thebottom of the pot I, and in the small lower chamber 22. The parts are soproportioned that the tripolT level is only slightly higher than theoperating oil level, and the volume of fuel in the bottom of the pot is,therefore, quite small `and can be burned olf without undue smoking oroverheating of the burner.

In view of the fact that the bottom 2 of the pot is higher than thebottom of the chamber 20 of the float 22, very little fuel will be fedinto the pot, as the fuel in it is burned off. Thus, in

bottom. No oil enters the float chamber after the re goes out, and afterthe oil in the pot reaches the indicated tripoif level.

. The oil may be metered drop by drop as it flows from the float chamberto the lower chamber 22, maintaining a rate of ow satisfactory for a lowturndown or pilot combustion. The device `controlling -the admission ofsuch liquid fuel to the primary float chamber, a float said primaryfloat chamber, an actuating connection between said oat and said valve,adapted to closesaid valve in response to a predetermined excess levelof fuel in the primary float chamber, a secondary float chamberat thegeneral level of the bottom of the burner, in communication with saidprimary iloat chamber, a fuel delivery pipe extend- -ing from saidsecondary ioatl chamber to the burner, said pipe constituting the soleavenue of delivery of liquid fuel to the burner from theprimary floatchamber, a valve in the. primary 1 oat chamber, adapted to control thevolume of flow of liquid fuel from the .primary chamber to the secondarychamber and thus to the burner, means for varying the settingv of saidvalve, a float in said secondary chamber, responsive to the level offuel in said secondary chamber and in the bottom of the burner, and anactuating connection between said float in the secondary chamber and thevalve for controlling the flow of fuel into the primary chamber.

2. In combination, in control means for liquid fuel burners, a burnerelement having a closed bottom and a circumferential side wall, andmeans for delivering liquid fuel to the burner element, including aprimary fuel chamber, a secondary fuel chamber in communication withsaid primary fuel chamber, a fuel pipe extending from said secondaryfuel chamber to the burner element, said secondary fuel chamberextending above and vrbelow the normal range of level of liquid fuel inthe burner element, means for controlling the inflow of liquid fuel tothe primary fuel chamber, including a movable control valve and meansfor actuating it, a float in said secondary fuel chamber andan actuatingconnection between the float and said control valve for the primarychamber, said float in said secondary fuel chamber being directlyresponsive to fluctuations of the level of a body of liquid lfuel whichextends continuously from the interior of the secondary fuel chamber,through said fuel pipe, to the interior of the burner element.

3. In combination, in control means for liquid fuel burners, a burnerelement having a closed.

bottom and a circumferential side wall, and means for delivering liquidfuel to the burner element, including. a primary fuel chamber, av

secondary fuel chamber in communication with said primary fuel chamber,a fuel pipe extending from said secondary fuel chamber to the burnerelement, said secondary fuel chamber extending above and below thenormal range of level of liquid fuel in the burner element, means forcontrolling the inflow of liquid fuel to the primary fuel chamber,including a movable control valve andmeans for actuating it, a float insaid secondary fuel chamber and an actuating connection between saidfloat and the control valve for the primary chamber, said float in saidsecondaryfuel chamber being directly responsive to fluctuations of thelevel'of a body of liquid fuel which extends continuously from theinterior of the secondary fuel chamber, through said fuel pipe, to theinterior of the burner element, the horizontal cross-sectional area ofthe secondary fuel chamber being substantially smaller than that of theburner element.

4. 'In combination, in control means for liquid fuel burners, a burnerelement having a closed bottom and a circumferential side wall, andmeans for delivering liquid fuel to the burner element, including aprimary fuel chamber, a secondary fuel chamber in communication withsaid primary fuel chamber, a fuel pipe extending from said secondaryfuel chamber to the burner element, said secondary fuel chamberextending above and below the normal range of -level of liquid fuel inthe burner element, means for controlling the inflow of liquid fuel tothe primary fuel chamber, including a movable control valve and meansfor actuating it, a float in said secondary fuel chamber and anactuating connection between 4said float and the control valve for theprimary chamber, said float in said secondary fuel chamber beingdirectly responsive to fluctuations of the level of a body of liquidfuel which extends continuously from the interior of the secondary f uelchamber, through said fuel pipe, to the interior ofthe burner element,the secondary fuel chamber being located at a level substantially belowthat of the primary fuel chamber.

5. In combination, in control means for liquid fuel burners, a burnerelement having a closed bottom and a circumferential `side wall, andmeans for delivering liquid fuel to the burner element, including aprimary fuel chamber, a secondary fuel chamber in communication withsaid primary fuel chamber, a fuel pipe extendingl fuel chamber,including a movable control valve and means for actuating it, a float insaid secondary fuel chamber and an actuating connection between saidfloat and the control valve for the primary chamber, said float in saidsecondary fuel chamberA being directly responsive to fluctuations of thelevel of a body of liquid fuel which extends continuously from theinterior of the secondary fuel chamber, through said fuel pipe, to theinterior of the burner element, and means for varying the rate of flowof liquid fuel from the primary fuel chamber to the secondary fuelchamber. y

6. In combination, in control means for liquid fuel burners, a burnerelement having a closed bottom and a circumferential side wall, andmeans for delivering liquid fuel to the burner element, including aprimary fuel chamber and a secondary fuel chamber in communication withsaid primary fuel chamber, the secondary fuel chamber being locatedbelow the primary fuel chamber, a liquid fuel duct extending from theprimary to the secondary fuel chamber, means associated with the primaryfuel chamber for controlling the rate of liquid fuel flow through saidduct to said secondary chamber, 'a fuel pipe extending from thesecondary fuel chamber to the burner element, said secondary fuelchamber extending above and belowI the normal range of level of liquidfuel in thev burner element, means for controlling the inflow of liquidfuel to the primary fuel chamber, including a movable control valve atsaid primary chamber and means for normally actuating it, and additionalmeans for actuating it including a float in said secondary fuel chamberand an actuating connection extending from the secondary fuel chamber tothe primary fuel chamber, said float being directly responsive tofluctuations of the level of a body of liquid fuel which extendscontinuously from the secondary fuel chamber, through said fuel pipe, tothe interior of the burner element.

JAMES L. BREESE. BRUCE HAYTER..

